Multi zone cementitious product and method

ABSTRACT

A multi-zone cementitious product, which includes a base zone made of a first cementitious material composition and forming a portion of the product. At least one facing zone is adjacent to and bonded to the base zone, the facing zone made of a second cementitious material composition and forming at least one exterior face of said product which is visible when the product is installed. A disrupted boundary layer is between the facing zone and the base zone, and includes material from both the facing zone and the base zone. The disrupted boundary layer bonds the facing zone to the base zone. The facing zone has a thickness sufficient to prevent the base zone from being visible when the product is installed.

FIELD OF THE INVENTION

The present invention relates generally to the field of cementitiousproducts. More particularly, the present invention relates to amulti-zone cementitious product having a plurality of zones, each zonehaving a different material composition and methods for producing it.

BACKGROUND

Cementitious products are used throughout the world in buildings, roads,and infrastructures in both structural and non-structural uses. Typicalcementitious materials used in producing cementitious products includebut are not limited to mixtures of cement, fly ash, water, sand, gravel,and/or rock. Of course, other components including plasticizers, waterproofing agents, cross linking agents, dyes, colorants, pigments, etc.may also be added to the cementitious material depending upon thedesired physical characteristics. Two basic categories of cementitiousproduct production are used and are the “wet cast” and “dry cast”methods.

The wet cast method uses a fluid mixture of cementitious materials thatis poured in place such as a road or driveway, poured into a form suchas a bridge support or reinforced building support, or poured into amold to produce artwork. Wet cast cementitious material is characterizedby a medium to high slump; or water to cement ratios greater thanapproximately 0.35. Typically, a wet cast product is separated from itsform or mold only after cementitious curing.

The dry cast method uses a viscous mixture of cementitious materialsthat is typically formed in molds or extruded under materialdensification techniques involving vibration, vacuum, and/or significantforming force. Most high volume cementitious building products such asbrick, paver, block, retaining wall block, tile, etc. are manufacturedusing a dry cast method. Dry cast cementitious material is characterizedby a negative slump, zero slump, or low slump; or water to cement ratiosless than approximately 0.35. Typically, a dry cast product is separatedfrom its form or mold after the forming process and cures in a separatelocation which in turn enables mass production of dry cast productswithout the material costs associated with having a mold that is usedthroughout the curing process.

Cementitious mixtures and resulting products may vary from lowercost—utilitarian products to higher cost—market preferred or aestheticproducts. Typical cementitious products are the same materialthroughout, even though only a small portion of the products will bevisible when they are finally installed. For example, facing bricks usedin home construction may only have one or two sides visible afterinstallation, but the entire brick is make of the relatively high costmaterial. There is a need, therefore to have a product wherein only thevisible faces are made of the higher cost material, with lower costmaterial on the inside of the product.

So called “composite” products are known in the art. Typical compositeproducts either join a less expensive base material to a more expensivemarket preferred facing material by bonding cured base and cured facingcomponents in a secondary operation or involve some composite productsformed with base and/or facing materials using a high percentage ofexpensive resins, epoxies, or other non-cementitious binding materials.Thus, there is a need for an affordable—market preferred or aestheticcomposite cementitious based product that does not use non-cementitiousbinders to hold the disparate materials together.

SUMMARY

The present invention relates to a multi-zone cementitious product,which includes a base zone made of a first cementitious materialcomposition and forming a portion of the product. At least one facingzone is adjacent to and bonded to the base zone, the at least one facingzone made of a second cementitious material composition and forming atleast one exterior face of said product which is visible when theproduct is installed. A disrupted boundary layer is between the at leastone facing zone and the base zone including material from both the atleast one facing zone and the base zone. The disrupted boundary layerbonds the at least one facing zone to the base zone. The at least onefacing zone has a thickness sufficient to prevent the base zone frombeing visible when the product is installed.

The invention further provides a method for making a multi-zonecementitious product, including the preparation of a cementitiousmaterial. A multi-forming machine is provided, having a base conveyor,at least one side conveyor, at least one top former, and at least onematerial input section upstream of the at least one top former forming acavity through which cementitious material may flow. The cementitiousmaterial is deposited onto the base conveyor in the material inputsection. The cementitious material is passed under the top former, whichforms an uncured slab between the top former, the base conveyor, and theat least one side conveyor. The uncured slab is ejected from themulti-forming machine. The slab is then cut to form an uncuredmulti-zone cementitious product, and the uncured multi-zone cementitiousproduct is then cured.

The invention also provides a method for making a multi-zonecementitious product, including the preparation of a first cementitiousmaterial and a second cementitious material. A molding machine isprovided, including a mold with at least one mold cavity, a first andsecond hopper, and at least one feed carriage, the feed carriage havinga plurality of feed cavities. The first hopper is filled with the firstcementitious material, and the second hopper is filled with secondcementitious material. The first cementitious material is transferredfrom the first hopper into at least one of the plurality of feedcavities, and the second cementitious material is transferred from thesecond hopper into at least one of the plurality of cavities. A transferplate is inserted under the mold. The feed carriage is moved over themold. At least one zone separator is inserted into the mold cavity, thefirst and second materials are deposited into the mold cavity, separatedby the zone separator, and the zone separator is removed from the moldcavity. The feed carriage is returned to a position under the first andsecond hoppers. A forming force is applied to the mold to form anuncured multi-zone cementitious product. The uncured multi-zonecementitious product is ejected from the mold onto the transfer plate,and the uncured multi-zone cementitious product is cured.

It will be understood by those skilled in the art that one or moreaspects of this invention can meet certain objectives, while one or moreother aspects can lead to certain other objectives. Other objects,features, benefits and advantages of the present invention will beapparent in this summary and descriptions of the disclosed embodiment,and will be readily apparent to those skilled in the art. Such objects,features, benefits and advantages will be apparent from the above astaken in conjunction with the accompanying figures and all reasonableinferences to be drawn therefrom.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of one embodiment of a multi-zonecementitious product in accordance with the invention;

FIG. 2 is perspective view of another embodiment of a multi-zonecementitious product in accordance with the invention;

FIG. 3 is perspective view of another embodiment of a multi-zonecementitious product in accordance with the invention;

FIG. 4 is perspective view of another embodiment of a multi-zonecementitious product in accordance with the invention;

FIG. 5A is perspective view of another embodiment of a multi-zonecementitious product in accordance with the invention;

FIG. 5B is top view of the multi-zone cementitious product of FIG. 5A;

FIGS. 6A-6D are top views of additional embodiments of a multi-zonecementitious product in accordance with the invention;

7A-7C are front views of additional embodiments of a multi-zonecementitious product in accordance with the invention;

7D-7F are top views of the multi-zone cementitious products of FIGS.7A-7C respectively;

FIGS. 8A-8D are top views of additional embodiments of a multi-zonecementitious product in accordance with the invention;

FIG. 9A is a perspective view of an additional embodiment of amulti-zone cementitious product in accordance with the invention;

FIG. 9B is a side view of the multi-zone cementitious product shown inFIG. 9A;

FIGS. 10A-10B are side detail views of the multi-zone cementitiousproduct of FIG. 1 showing a boundary before and after boundarydisruption;

FIGS. 11A-11B are side views of another embodiment of the multi-zonecementitious product showing a boundary before and after boundarydisruption;

FIGS. 12A-12F are side views of additional embodiments of multi-zonecementitious products in accordance with the invention;

FIG. 13 is a perspective view of a zone separator in accordance with theinvention;

FIG. 13A is a side view of the zone separator shown in FIG. 13;

FIG. 14 is a partially schematic perspective view of a multi-formmachine in accordance with the invention;

FIG. 15 is a partially schematic side view of the multi-form machine ofFIG. 14;

FIG. 16A is a top schematic view of the multi-form machine of FIG. 14with side conveyors adjusted to a narrow arrangement;

FIG. 16B is another top schematic view of the multi-form machine of FIG.14 with side conveyors adjusted to a wide arrangement;

FIG. 17 is a side schematic view of another embodiment of a multi-formmachine in accordance with this invention;

FIG. 18 is a perspective view of a multi-formed slab in accordance withthe invention;

FIG. 19 is a schematic perspective view of a horizontal coining chamberin accordance with the invention;

FIG. 20 is a top schematic view of a horizontal coining chamber inaccordance with the invention;

FIG. 21 is a schematic perspective view of a vertical coining chamber inaccordance with the invention;

FIG. 22 is a top schematic view of a vertical coining chamber inaccordance with the invention;

FIG. 23 is a top schematic view of a multi-form slab cutter inaccordance with the invention;

FIGS. 24A-24H are front views of a multi-form process showing one methodof making a multi-zone cementitious product in accordance with theinvention;

FIGS. 25A-25H are front views of another multi-form process showinganother method of making a multi-zone cementitious product in accordancewith the invention;

FIG. 26 is a partially schematic top view of a multi-form machine withbuckets in according with the invention;

FIGS. 27A1-27A7 are top views of a multi-form process showing anothermethod of making multi-zone cementitious product in accordance with theinvention;

FIGS. 27B1-27B7 are front views of the multi-form process of FIGS.27A1-27A7;

FIG. 28A is a perspective view of a mold in accordance with theinvention;

FIG. 28B is a top view of the mold shown in FIG. 28A;

FIG. 29A is a perspective view of a zoned material supply system inaccordance with the invention;

FIG. 29B is a top view of the zoned material supply system shown in FIG.29A;

FIG. 29C is a section view of the zoned material supply system shown inFIG. 29A, taken generally along line 29C-29C;

FIG. 30A is a perspective view of another embodiment of a mold inaccordance with the invention;

FIG. 30B is a top view of the mold shown in FIG. 30A;

FIG. 31A is a perspective view of another embodiment of a mold inaccordance with the invention;

FIG. 31B is a top view of the mold shown in FIG. 31A;

FIG. 32 is a schematic view of a multi-zone mold machine in accordancewith the invention showing two hoppers, two feed carriages, a mold, anda ram;

FIG. 33 is another schematic view of the multi-zone mold machine of FIG.32;

FIG. 34 is another schematic view of the multi-zone mold machine of FIG.32;

FIG. 35 is another schematic view of the multi-zone mold machine of FIG.32;

FIG. 36 is another schematic view of the multi-zone mold machine of FIG.32;

FIG. 37 is another schematic view of the multi-zone mold machine of FIG.32;

FIG. 38 is another schematic view of the multi-zone mold machine of FIG.32;

FIG. 39 is another schematic view of the multi-zone mold machine of FIG.32;

FIG. 40 is another schematic view of the multi-zone mold machine of FIG.32;

FIG. 41 is another schematic view of the multi-zone mold machine of FIG.32;

FIG. 42 is a perspective view of an agitator in accordance with theinvention;

FIGS. 43A-43B are schematic views of additional embodiments of agitatorsin accordance with the invention;

FIG. 44 is a schematic view of another embodiment of a multi-zone moldmachine in accordance with the invention showing two hoppers, a firstfeed carriage, a second feed carriage having metering rollers, a mold,and a ram;

FIG. 45 is a perspective view of a multi-zone slab in accordance withthe invention;

FIG. 46 is a schematic perspective view of an extrusion chamber inaccordance with the invention;

FIG. 47 is another schematic perspective view of the extrusion chambershown in FIG. 46; and

FIG. 48 is a side schematic view of an extrusion chamber shown in FIG.46 showing the process for extruding a slab through the extrusionchamber.

DETAILED DESCRIPTION

FIGS. 1-4 show similar embodiments of a multi-zone cementitious product100 in accordance with the invention. The multi-zone cementitiousproduct 100 includes a plurality of material volume zones, each zonehaving a different material composition. The embodiments shown in FIGS.1-4 are multi-zone cementitious products 100 having a base zone 102 andat least one facing zone 104.

The multi-zone cementitious product 100 would typically be used toprovide preferred marketplace aesthetics or product features withdecreased material cost. Decreased material cost is achieved by havingthe preferred marketplace aesthetics or preferred product features onlyin zones that are potentially visible when the multi-zone cementitiousproduct 100 is installed rather than having a product made entirely ofmaterial having the preferred marketplace aesthetics and/or productfeatures.

Base zone 102 may be made of a lower cost, non-facing cementitiousmaterial having less preferred marketplace aesthetics or preferredproduct features. Facing zone 104, however, may be made of higher costcementitious material with material added to the mixture to create adesired aesthetic effect or product features. For example, the base zone102 may include less expensive cementitious types or lower levels ofmore expensive cementitious types, less expensive or coarser aggregatetypes or lower levels or more expensive or finer aggregate types, lessexpensive color pigment types or lower levels of pigments, lessexpensive additive types or lower levels of expensive additives, ordifferent water levels, and may further include other material. Thefacing zone 104, on the other hand, may include more expensivecementitious types or higher levels of more expensive cementitioustypes, more expensive or finer aggregate types or higher levels of fineraggregate types, more expensive color pigment types or higher levels ofcolor pigments, more expensive additive types or higher levels ofexpensive additives, and different water levels, and may further includeother differing material types or levels of those materials. Anycementitious product including zones of different material compositionmay be used without departing from the invention.

As shown, the multi-zone cementitious product 100 may be formed by anysuitable wet cast or dry cast technique such as multi-forming, molding,or extrusion. During the formation process, each technique includescertain common steps that enable the creation of a multi-zonecementitious product 100 in accordance with the invention. Such stepsinclude mixing more than one cementitious material composition, layeringor segmenting the cementitious materials to create more than one zone ofmaterial, and vibrating and/or vacuum (densification), forming force(densification), and curing the cementitious product.

During formation of the multi-zone cementitious product 100, a boundaryzone 106 forms between the base zone 102 and each of the facing zones104. The boundary zone 106 is a cementitious material transition andforms a bonding layer between the base zone 102 and facing zone 104. Inorder to sufficiently bond the base zone 102 to the facing zones 104without the addition of bonding agents such as polymer or adhesive, theboundary zone 106 must be disrupted, meaning the material in the basezone 102 is intermingled with the material in the facing zones 104. Thisdisrupted boundary layer 106 enhances the bond between the base zone 102and the facing zones 104. Such enhancement is necessary to ensure thatthe bond between the base zone 102 and facing zone 104 is strong.

FIG. 1 shows one embodiment of a multi-zone cementitious product 100 inaccordance with the invention. The embodiment shown in FIG. 1 has a basezone 102 with a facing zone 104 deposited on one side, the top in FIG.1, of the base zone. The boundary zone 106 forms between the base zone102 and the facing zone 104. The facing zone 104 has a facing side 108that forms an exterior surface of the facing zone and is preferably anexterior surface visible after product installation. The product 100could be a masonry brick, or it could be a cementitious slab 100 whichin use could be horizontally oriented such as a cementitious floor, orvertically oriented such as a cementitious wall.

The embodiment shown in FIG. 2 has a facing zone 104 that wraps aroundtwo sides of the base zone 102 resulting in two adjacent facing sides108, 110. In the embodiment shown, the two adjacent facing sides 108,110 are the top and front of the multi-zone cementitious product 100,but the adjacent facing sides could be on any two adjacent sides withoutdeparting from the invention. FIG. 3 shows an embodiment having threeadjacent facing sides 108, 110, 112. Additionally, embodiments havingmore or less adjacent facing sides or partial facing sides may be formedwithout departing from the invention.

Alternative embodiments of the present invention may include but are notlimited to other cementitious products such as concrete block, pavers,retaining wall block, tile, roofing products, and other cementitiousbuilding products. Examples showing some alternative embodiments areshown in FIGS. 4-8.

FIG. 4 shows an additional common embodiment of a multi-zonecementitious product in accordance with the present invention. FIG. 4shows a cementitious retaining wall block 300 with base zone 302surrounded by a perimeter facing zone 304, and having adjacent boundaryzone 206 and facing sides 308. Of course, any configuration of facingsides may be used without departing from the invention.

FIGS. 5A, 5B, 6A and 6B show other embodiments of a multi-zonecementitious product 400 in accordance with the invention, having a basezone 402, at least one facing zone 404, and boundary zone 406. In theembodiment shown in FIGS. 5A-5B, facing zones 404 form a perimeteraround base zone 402, and facing side(s) 408 may be visible afterproduct installation. Multi-zone cementitious product 400 may be madewith or without core holes 410. FIGS. 6A-6D show some alternativeembodiments of multi-zone cementitious product 400, each with one ormore facing zones 404 forming less than a total perimeter around thebase zone 402.

FIGS. 7A-7F show yet another embodiment of the invention of a multi-zonecementitious product 500 with base zone 502, at least one facing zone504, and boundary zone 506. Facing side(s) 508 provide potential facingsurfaces after product installation. FIGS. 7A and 7D show a multi-zonecementitious product 500 with a top facing zone 504 to provide facingside 508. Top facing zone 504 has a thickness T1 which allows theproduct top and product partial side surfaces of facing zone 504 to beused as visible surfaces after product installation.

FIGS. 7B and 7E show one top facing zone 504 providing top facing side508 and other facing zones providing adjacent facing sides. One or morefacing zones 504 enable adjacent facing zones to encase the perimeteraround base zone 502. Facing sides 508 may or may not extend to entirelength of the product 500 side. Top facing zone 504 has a thickness T2which allows the top and side surfaces of facing zone 504 to be visibleafter product installation. Side facing zone has a thickness T3 whichallows the side surfaces of facing zone 504 to be used as visiblesurfaces after product installation. Adjacent facing sides 508 may ormay not extend the whole length of the product 500.

FIGS. 7C and 7F show a product 500 having one top facing zone 504providing top facing side 508 and other facing zones providing adjacentfacing sides. One or more facing zones 504 enable adjacent facing sides508 to encase less than the perimeter around base zone 502. Adjacentfacing sides 508 may or may not extend the whole length of the product500.

FIGS. 8A-8D show other embodiments of multi-zone cementitious products600 in accordance with the invention having base zone 602, one or morefacing zones 604, and a boundary zone 606. Facing sides 608 providepotential facing surfaces after product installation. FIG. 8A showsmulti-zone cementitious product 600 with one or more facing zones 604 toprovide facing sides 608 to provide a perimeter around base zone 602.FIG. 8B shows one side facing zone 604 providing facing side 608. Frontfacing zone has a thickness T4 which provides the product front andproduct partial top and product partial side surfaces of facing zone 604to be visible after product installation. FIG. 8C shows one front facingzone providing front and adjacent facing sides 608. One or more facingzone 604 causes adjacent facing sides to encase less than the perimeteraround base zone 602. Facing sides 608 may or may not extend the entiredepth of the product side. FIG. 8D shows one top facing zone 604providing product top facing side 608 and other facing zones providingadjacent facing sides. One or more facing zone 604 enables adjacentfacing sides to provide product front facing sides and product sidefacing side to encase less than the perimeter around base zone 602.Facing sides 608 may or may not extend to whole depth of the productside.

FIGS. 9A-9B show another embodiment of the invention a multi-zonecementitious product 700 with base zone 702, facing zone 704, andboundary zone 706. Facing side 708 provides a facing surface afterproduct installation. Facing zone 704 has a thickness sufficient toallow only material in facing zone 704 to show after productinstallation. As shown, boundary zone 706 has greater thickness at thebottom of the multi-zone cementitious product 700 than at the top of theproduct. Thus, the transition of the boundary zone 706 to the base zone702 is disposed at an angle 710 with respect to the vertical plane ofthe product. The angle 710 provides enhanced bonding of the zones duringvibration and densification of the product 700.

In each of the embodiments shown, the boundary zones 106, 206, 306, 406,506, 606, 706 are achieved during the densification and/or formingprocess of the multi-zone cementitious product 100, 200, 300, 400, 500,600, 700 using vibration, vacuum, and/or forming force and, if required,mechanically disrupting the surface of one zone prior to and/orconcurrently with applying a second zone prior to curing. Vacuuming maybe a step in the cementitious product forming process that reduces airpockets in the product and densifies the cementitious materials.Vibrating is a normal step in the cementitious product forming processthat also reduces air pockets in the product and densifies thecementitious materials. However, in the present invention, the vibrationstep also aids in the creation of the boundary zone 106. Applyingforming force is another normal step in the cementitious product formingprocess that also reduces air pockets in the product and densifies thecementitious materials. Like the vibration step described above, theapplication of forming force also aids creation of the boundary zone106. In the present invention, zones of material may be deposited andformed at the same time or at different times. The formation of eachzone may cause a film layer to form on any formed surface of the zone.The film layer is generally smooth and inhibits material bonding with anadditional zone at the boundary layer.

FIGS. 10A-10B show detail views of a boundary zone 106 of FIG. 1, as anexample. This description applies to all other embodiments as well. FIG.10A shows base zone 102, facing zone 104, and boundary 105. Bondingbetween zone 102 and 104 is achieved and/or enhanced by disrupting theboundary 105 between zones to intermingle materials within base zone 102and facing zone 104 to form a boundary zone 106 (see FIG. 10B). Thefacing zone 104 has an initial thickness 120 that decreases as a resultof the formation of the boundary zone 106. After boundary disruption,facing zone 104 has a new and smaller thickness 122. Smaller thickness122 is specifiable and should be designed to prevent undesirablephysical features from revealing in the event of any chippage or otherminor and normal damage that may occur to facing zone 104. For example,if base zone 102 contains a non-colored cementitious materialcomposition and facing zone 104 contains a colored cementitious materialcomposition, then smaller thickness 122 should be large enough to allownormal chipping of the facing zone 104 without exposing the boundarylayer 106 or base zone 102. The example shown in FIGS. 10A-B isillustrative of the boundary between two zones, but additional zones maybe layered one on top of another, each of which would have a boundarylayer formed between them.

Disruption of the boundary 105 may be achieved by any suitable meansincluding but not limited to preventing a film from forming at theboundary 105, removing a film at the boundary 105, physically moving orvibrating one zone with respect to another zone in a motionsubstantially parallel to the boundary 105, compacting the zonestogether, physically moving or vibrating the zones in a direction notparallel to the boundary 105. Of course, the techniques described may beused individually or in combination to achieve the level of disruptiondesired. The techniques described are simply examples, and othertechniques for disrupting the boundary 105 may be used without departingfrom the invention.

Additionally, a bonding layer may be deposited between zones to enhancezone bonding. The bonding layer may include a number of materialsincluding but not limited to cellulous fiber, polymer fiber, carbonfiber, glass fiber, and/or cementitious material having differentmaterial content and/or moisture content than the zones. The bondinglayer may include any material that enhances zone bonding withoutdeparting from the invention. Of course, base zone 102 and facing zone104 may also include additional materials that improve bonding of thezones.

Typical vibration processes include vibration in only the vertical axis,which enables the reduction of material voids during densification. Inthe present invention, however, vibration in multiple axes may be usedto sufficiently disrupt boundaries 105 of differing orientations. Theboundary layer 106 is best formed when direction of vibration and thedirection of forming force is not parallel to the boundary layer. Forexample, in a cementitious product with vertical boundary layers 106,only vertical vibration and/or forming force may not be enough toadequately disrupt the boundary layer 106. In the present embodiment,this issue is overcome by forming the base zone 102 and facing zones 104so that the boundary 105 is not parallel to the vibration direction.

FIGS. 11A-B show one example of a non parallel boundary 105. FIG. 11Ashows the multi-zone cementitious product 100 at an early stage offormation, prior to any vibration or densification. In the embodimentshown, facing zone 104 is added to a product forming cavity before basezone 102 is added on top of the facing zone. If both zones 102, 104 areloosely placed within the cavity, then initial vibration and formingforce will adequately disrupt the boundary 105 to form the boundary zone106. As the densities of the cementitious material compositionsincreases during vibration, vacuuming, or forming force densification,the disruption of the boundary 105 will be more effective if theboundary 105 is non-parallel to the direction of vibration anddensification force. As shown, the facing zone 104 includes one side ofthe product. To allow sufficient bonding, an offset angle 111 is addedto the boundary 105 so that it is non-parallel to a vertical vibrationand densification force.

If facing zone 104 is slightly densified prior to adding base zone 102then a film layer that could result from that densification may bemechanically disrupted to pierce the film layer, thereby exposingunderlying cementitious material. Next, after base layer 101 is added ina low density manner, the whole product can be densified and formed.This technique of mechanically disrupting a layer to pierce the filmlayer may be used for zones in any orientation.

If zones are formed in a low density manner, a zone separator may beused as a barrier between zones to maintain zone integrity. The zoneseparator can then be withdrawn to prevent the formation of a film layerat the boundary prior to final vibration and/or final forming force. Thezone separator may be made of any suitable material and may furtherinclude fingers, prongs, stakes, or any other form to furthermechanically disrupt or rake the boundary 105.

Typically, product densification is achieved by four factors: vibration,vacuum, initial forming force, and final forming force. Disruption ofboundary 105 may be achieved most easily when the vibration and/orforming force is perpendicular to the boundary. To achieve adequatedisruption the relative direction of initial vibration and forming forcecould be from one or more directions and final vibration and/or formingforce could be in one of more other directions.

FIGS. 12A-F show some illustrative embodiments of configurations ofboundary 105. For example, in a cementitious product with a front andside forming the facing zones 104, the front boundary 105A will runperpendicular to the vertical vibration and/or forming force direction.The vertical boundary 105B, however, does not run parallel to thedirection of vibration. Rather, the vertical boundary 105B has a profilethat is not parallel to the direction of vibration, which provides foradequate disruption of the vertical boundary 105B. Of course, anyconfiguration of boundary layer and/or vibration direction may be usedwithout departing from the invention. Additionally, any suitable meansfor disrupting the boundary 105 may be used including but not limited toraking and/or mechanical displacement without departing from theinvention.

It should be apparent that when the boundary zone 106 is formed, and thematerial from the base zone 102 intermingles with the facing zone 104,the desired aesthetic qualities of the facing zone and/or preferredproduct features may be degraded. Thus it is necessary that the facingzones 104 have a thickness such that the disrupted boundary layer 108does not affect the exterior decorative face of the cementitious product100. The thickness of the facing zone 104 will vary depending on thecementitious mixture of both the base zone 102 and the facing zone, aswell as other factors including but not limited to vibration force,vibration amplitude, vibration time, vibration direction relative toboundary 105, forming force, forming force interval, forming forcedirection relative to boundary 105, mechanical disruption of the zones104, 102, other disruption means, etc.

FIGS. 13 and 13A shows one embodiment of a raking tool 260. In theembodiment shown, the raking tool 260 is integral with a zone separator900 and has prongs 262 protruding from the bottom end of the zoneseparator. The prongs 262 may be on either side or both sides of thezone separator 900 and may disrupt material on the base zone 102 and/orthe facing zone 104. Relative placement and spacing of the prongs 262,the amount that the prongs protrude, and movement of the raking tool 260may vary to suit any manufacturing process, product shape, andcementitious material used to make a multi-zone cementitious product 100in accordance with the invention.

As described earlier, the multi-zone cementitious product, such as theproduct 100 shown in FIG. 1, may be formed by any suitable means,including but not limited to multi-forming, molding, or extrusion.Multi-forming products is a process wherein successive layers orsegments of material are deposited onto a slab, thereby building aproduct in layers. The basic multi-forming process involves a series ofconveyers, rollers, screeds, and/or skimmers that shape cementitiousmaterial as it moves from the beginning of the multi-former to the end.

FIG. 14 shows a basic multi-forming machine 150 that can either producea cementitious product or a cementitious slab to be used in one or moresecondary processes to produce a cementitious product. Basicmulti-forming machine 150 has a continuous “U” shaped channel 152 thatcontains, forms, and densifies cementitious materials deposited into thechannel. A forming base conveyor 154 forms the bottom of the “U” andforms the base of the multi-zone cementitious product. Forming sideconveyors 156 create the two sides of the “U” which form the sides ofthe multi-zone cementitious product. Finally, in the embodiment shown, aforming top roller 158 forms the top side of the multi-zone cementitiousproduct. Alternative embodiments of a multi-forming machine 150 mayreplace the forming top roller 158 with one or more additional rollers,a screed, and/or skimmer.

A cementitious material input section 160 is supplied upstream of theforming top roller 158. Cementitious material is deposited onto theforming base conveyor 154, passing under the forming top roller 158,forming a slab 162. The formation of the slab 162 is controlled by theforming side conveyors 156 and the forming top roller 158. Rather thandepositing the cementitious material directly onto the forming baseconveyor 154, a transfer plate could be placed onto the forming baseconveyor before the cementitious material is deposited thereon. Thetransfer plate could be used as a platform on which the slab 162 isformed and to transfer the slab and/or multi-zone cementitious product100 to a curing accumulation system or storage thereby reducing stresson the product while it is in an uncured state. The transfer plate usedwithin the multi-forming machine 150 and in any secondary process(es)could be thin such as a piece of sheet metal that could in turn be addedon to a thicker/stiffer transfer plate. Further, the transfer platecould be wider than the slab 162 and lay in a gap between the formingbase conveyor 154 and the forming side conveyors 156.

In the embodiment shown, the forming base and side conveyors 154, 156include structural wear plates (not shown) that stiffen the conveyorsbetween the conveyors' pulleys 164 to aid formation of the slab 162. Thewear plates are adjustable along the length of the conveyor to providecompressive force during forming of the slab 162, and may provideclearance to release pressure on the slab 162 downstream so that it maybe removed from the multi-forming machine 150. Additionally, sections ofthe structural wear plates may vibrate to enable belt vibration andcementitious densification. Similarly, the top forming roller 158 mayvibrate to aid densification of the slab 162.

FIG. 15 shows a side view of the multi-forming machine 150. As shown,vibration plate(s) 166 can be located underneath forming base conveyor154 and/or inside or connected to the slab facing portion of the belt offorming side conveyors 156. Forming top roller 158 exerts pressuresagainst slab 162 in order to create forming forces. The height of slab162 is determined by one or more forming top rollers 158 which could besubstituted with one or more screed, one or more skimmers, and/or one ormore series of rollers encased within a belt to aid or provide formingpressure.

As shown in FIGS. 16A and 16B, the distance between forming sideconveyors 156 can be adjusted to determine the width of the slab 162. Asmaller separation 51 is shown in FIG. 16A, whereas a larger separationS2 is shown in FIG. 16B. It should also be noted that the surface speedof the forming side conveyors 156 may be adjusted and could be eitherslower, the same, or faster than the surface speed of the forming baseconveyor 154. Such adjustment allows for varying cementitious mixdesigns, textures, and other forming options.

FIG. 17 shows a slab 162 being made on the multi-forming machine 150. Inthe embodiment shown, a first deposit of cementitious material is addedto a first input section 160, wherein the cementitious material passesunder a first forming top roller 158, which forms the bottom portion ofthe slab 162. In the embodiment shown, the first forming top roller 158includes a profile that forms furrows in the bottom portion of the slab162, to accommodate the emplacement of core mandrels 170 within thefurrows. The first forming top roller 158 may also vibrate along withthe bottom or side belts to aid densification of the slab 162. A smalllengthwise gap is formed between core mandrels 170 that are lengthwiseadjacent, to allow cutting of the slab 162 at the gaps.

After the core mandrels 170 are inserted onto the bottom portion of theslab 162, another second deposit of cementitious material is added to asecond input section 161. The bottom portion of the slab 162 and thenewly deposited cementitious material pass under a second forming toproller 159 to form the top portion of the slab 162. The slab 162 is thencut at the lengthwise gap between core mandrels by a slab cutter 172 andaccumulated on a table or conveyer (not shown) to then complete one ormore secondary operations on the formed products. Uncured or “green”products are then processed elsewhere by either air curing the productor autoclave curing. It is also possible to support the core mandrels170 from a transfer plate rather than laying the core mandrels on thebottom portion of the slab 162. In such a configuration, onecementitious material input with vibration and forming tools could forcecementitious material between core mandrels to form the entire slab 162instead of forming the bottom portion of the slab, then adding the coremandrels 170, then adding the top portion of the slab.

After slab 162 is formed, it must undergo secondary processes to form afinal cementitious product. Such secondary processes may include but arenot limited to: final densification using vibration, vacuum, and/orforming force; final forming force to enable negative, zero, or lowslump cementitious material to be compressed to several thousand poundsper square inch; texturing; de-coring the slab 162 by removing the coremandrels 170; cutting the slab into individual products. FIG. 18 shows aslab 162 with mandrel core 170 within the slab.

FIG. 19 shows a horizontal coining chamber 180 which encases slab 162and achieves final densification via vibration, vacuum, and/or formingforce. Additionally, several types of texturing are possible. Chamberbase 182 is stationary and chamber side walls 184 and chamber top 186are moveable to allow for slab 162 insertion. Once inserted, chamberside walls 184 and chamber top 186 are then set for “green” productlength and width dimensions. One end of the chamber 180 receives an endcap and the other end of the chamber receives a ram to supply finalforming force. Chamber sides 184 may also adjust for smaller or largerproduct lengths and one or more spacers may be added on the chamber base182 or chamber top 186 for smaller and larger product widths. A textureplate could be added on the chamber base 182, chamber top 186, and/orchamber side(s) 184 to create a texture on the slab 162. The textureplate could be stationary within the horizontal coining chamber 180 ormove with the product. A gap 188 between chamber base 182 and chamberside walls 184 enables clearance for an overhanging transfer platewidth.

FIG. 20 shows the operation of the horizontal coining chamber 180, whichincludes the following steps: (1) The slab 162 is inserted onto thechamber base 182, the chamber side walls 184, and chamber top (notshown) are adjusted for desired “wet” dimensions, (2) the chamber endcap 190 is placed over one end of the chamber and a ram 192 is placedwithin the other side of the chamber, (3) a combination of formingvibration, vacuum, and/or forcing force completed product slabdensification, (4) the ram is withdrawn exposing the core mandrels 170due to slab densification, (5) the end cap is withdrawn and the coremandrels are extracted (from either side), (6) the distance between thechamber side walls increases slightly and the slab is ejected from thechamber.

FIGS. 21-22 shows a vertical coining chamber 280 and related operation.The vertical coining chamber 280 has a similar operation to thehorizontal coining chamber 180 and includes the following steps: (1) theslab 162 is inserted onto the chamber base 282, (2) the chamber sidewalls 284 and end caps 290 are put in place for desired “wet”dimensions, (3) the ram 292 is inserted in the chamber and appliesforming force, (4) a combination of forming vibration, vacuum, and/orforcing force is applied to complete slab densification, (5) one or moreend cap is removed and the core mandrels 170 are extracted (slight forceon the ram prevents fracturing of material during core mandrelwithdrawal), (6) the ram is withdrawn and any remaining end cap iswithdrawn, and (7) the distance between the chamber side walls increasesslightly and the slab is ejected from the chamber.

FIG. 23 shows a cutting operation which could be used on slabs 162ejected from the coining operation previously described. Slabs 162 areaccumulated from the coining operation and sent through a cutter 250,producing products such as the product 100 shown in FIG. 1, from theslab 162. The “green” products may then be sent to another location forfurther curing. Cutter 250 may be any suitable slab cutting deviceincluding but not limited to a rotary cutter or wire cutter. Theselection of cutter 250 may allow formation of desired textures on thesurface of the product.

The multi-forming process above is particularly well suited to achievinga multi-zone cementitious product such as the product 100 shown in FIG.1, in accordance with the invention. FIGS. 24A-24H and 25A-25H show twoapproaches to making a multi-zone cementitious product such as theproduct 100 shown in FIG. 1 using the multi-forming process. Bothapproaches show how an “L” shaped multi-zone cementitious product can bemade. FIGS. 24A-24H show facing zones 104 on the top and one side of theslab 162. FIGS. 25A-25H show facing zones 104 on the bottom and one sideof the slab 162.

Turning first to FIGS. 24A-24H, the steps of forming a multi-zonecementitious product such as the product 100 shown in FIG. 1 are shownwith relation to how material is built up in a multi-forming process tomake a finished product. The first step, shown in FIG. 24A, is to addmaterial for the bottom and one side facing zone 104 onto the formingbase conveyor 154. Second, as shown in FIG. 24B, furrows 171 are formedinto the material to prep for the addition of core mandrels 170. Third,as shown in FIG. 24C, the core mandrels 170 are placed into the furrows171 and raking of materials may occur. Fourth, as shown in FIG. 24D,materials are added for the remainder of the slab 162 including one sidefacing zone 104, but not a top facing zone 104. Fifth, as shown in FIG.24E, the material is prepped for the addition of a top facing zone 104.Sixth, as shown in FIG. 24F, material is added to form the top facingzone 104. Seventh, as shown in FIG. 24G, final sizing of the slab 162 isaccomplished and is transferred to a different location for secondaryoperations. Finally, as shown in FIG. 24H, after secondary operations,the slab 162 is cut into individual products and is cured.

FIGS. 25A-25H show a similar process to the one shown in FIGS. 24A-24H,but depositing the facing zone first provides for some differences inthe process. The first step, as shown in FIG. 25A, is to add facingmaterial to form a bottom facing zone 104 and simultaneously form a sidefacing zone 104. Second, as shown in FIG. 25B, the surfaces of thefacing zones 104 may be raked in preparation for the addition of asecond material. Third, as shown in FIG. 25C, non-facing material isadded on top of the facing zones 104 and the non-facing material hasfurrows 171 formed into the material to prep for the addition of coremandrels 170. Fourth, as shown in FIG. 25D, the core mandrels 170 areplaced into the furrows 171, and the non-facing material may be raked toprepare for the addition of more non-facing material. Fifth, as shown inFIG. 25E, the remaining non-facing material is added to complete theslab 162. Sixth, as shown in FIG. 25F, the slab 162 undergoesdensification and forming. Seventh, as shown in FIG. 25G, final sizingof the slab 162 is accomplished. Finally, as shown in FIG. 25H, the slab162 is cut into individual products and is transferred to a differentlocation for secondary operations and ultimately, curing.

An alternative multi-forming technique is shown in FIGS. 26-27 whereinindividual products are formed in “buckets” rather than forming a slabthat must be cut in a later operation into individual products. FIG. 26shows individual product buckets 350 which are formed by includinglocator protrusions 352 on forming side conveyors 156. The locatorprotrusions 352 mate with locator detents 354 at either end of bucketseparator 356. As the forming base conveyor 154 and forming sideconveyors 156 advance, the bucket separators advance 356 as well,essentially creating a moving mold cavity into which cementitiousmaterial may be deposited. As in the previous discussion ofmulti-forming techniques, a transfer plate (not shown) may be insertedonto the forming base conveyor 154 so that the products may be easilyremoved from the multi-forming machine 150. As the cementitious materialexits the multi-forming machine 150 it is not a slab 162 as in thepreviously described multi-forming technique. Rather, the cementitiousmaterial exits the multi-forming machine 150 as essentially formedproducts. The cementitious material may exit the multi-forming machine150 in groups of buckets 350 according to the length of the coremandrel(s) 170 that may span the group.

Of course, the products must undergo the same secondary operationspreviously described, but at the end of the secondary processes, thereis no cutting step required. By eliminating the cutting step, tighterdimensional tolerance and more precise texturing can be achieved.Additionally, more coarse material may be used because there is nocutting step involved. If vertical coining is used to apply formingforce, the ram 292 may be divided into individual rams that apply forceto each product between bucket separators 356. If coarse material suchas gravel were introduced to the slab 162, the larger aggregate wouldcause problems during the cutting step. As in the previously describedmulti-forming process, core mandrels 170 may be used with the bucketseparators 356. For example, the core mandrels 170 may be inserted intoeach bucket 350. Alternatively, the bucket separators 356 may includeholes that allow longer core mandrels 170 to pass through so that oneset of mandrels 170 can be used for a group of buckets 350. In eitherexample, each bucket 350 is individually densified, unlike a slab, wheredensification can be a continuous process as the slab passes through themulti-forming machine 150. After final densification and forming, thecore mandrels 170 would be removed and a group of formed product wouldbe sent on for curing. The bucket separators 356 would then be removedas curing permitted.

Another technique for forming a multi-zone cementitious product 100 inaccordance with the invention is to form the product on a moldingmachine. The steps necessary for creating a multi-zone cementitiousproduct 100 on a molding machine include: (1) mixing two or morecementitious materials, (2) transferring the mixtures into two or morehoppers or material holding areas near the mold, (3) supplying themixtures to zoned sections in a mold cavity, (4) disrupting the boundarybetween the zoned sections, (5) densification of the materials byvibration, vacuum, and/or forming force, (6) ejecting “green” productfrom the mold, and (7) curing the product.

Some examples of material supply scenarios include: (1) two or morecementitious materials are supplied simultaneously and materials enterthe mold cavity via gravity, agitation, and/or vibration, (2) two ormore cementitious materials are supplied simultaneously and materialsenter the mold cavity via a metering means, agitation, and/or vibration,(3) two or more cementitious materials are supplied alternately andmaterials enter the mold cavity via gravity, agitation, and/orvibration, and (4) two or more cementitious materials are suppliedalternately and materials enter the mold cavity via a metering means,agitation, and/or vibration which is a controlled variation of (2)above. Of course material could be added to the mold in any othercombination without departing from the invention.

Turning now to FIG. 28, a mold zone separator 900 is shown, whichenables multi-zone molding. The product is formed on top of a producttransfer plate 902 and then transferred on for curing. A product mold904 has a mold cavity 906 into which the mold zone separator 900 isinserted and retracted. Mold zone separator 900 is supported by atransfer means (not shown) which locates the mold zone separator 900above the mold cavity 906 prior to adding cementitious materials andremoves mold zone separator prior to a ram head (not shown) beinglowered onto cementitious materials in the filled mold 904 to provideforming force. Once mold zone separator 900 is inserted within the moldcavity 906, a facing mold cavity 908 and non-facing mold cavity 910 arecreated. Filling facing mold cavity 908 with cementitious facingmaterial and filling non-facing mold cavity 910 with cementitiousnon-facing materials aids in producing a multi-zone cementitious productsuch as the product 100 shown in FIG. 1. Of course, more than one moldzone separator 900 may be used during multi-zone molding. Using morethan one zone separator 900 may enable zone separation to be angledwithin the mold cavity such that the zone separators are not parallel tothe direction of vibration and thus aid disruption of the boundary layer106.

As is understood in the art, the embodiments described herein of themold refer to one mold which is likely used as part of a larger moldhaving a plurality of cavities. The embodiments described here focus ononly one such cavity but should not be taken to be limiting to onecavity molds only. Additionally, the zone separator 900 may take anyshape, and the deposition of materials into the product mold 904 may beused to achieve facing zones 104 on any desired side of the product.

FIG. 29 shows how material may be supplied to a product mold 904 toachieve a multi-zoned cementitious product such as the product 100 shownin FIG. 1. Zoned material supply system 920 is located relative to theproduct mold 904. The mold zone separator 900 is attached to thematerial supply system 920 and may extend from the material supplysystem into the mold cavity 906. Zoned material supply system 920 maycontain two or more cementitious materials separated by a materialsupply zone separator 922 to thus provide a facing material supplycavity 924 and non-facing material supply cavity 926.

The bottom of zoned material supply system 920 may contain one or morematerial supply cavity seals 928 to enable the release, controlledrelease, and/or stoppage of one or more cementitious material from thesystem. Material supply cavity seals 928 may also be used to levelcementitious materials to the top of the mold. Additionally, topmaterial supply cavity seals (not shown) may enable the input,controlled input, and/or stoppage of one or more cementitious materialinto the system. Material supply cavity seals 928 are shown as linear innature; they may also be louvers, shingles, and/or rotational in nature.

FIGS. 30 and 31 shows alternative configurations of the mold zoneseparator 900 to achieve products as described previously. FIG. 29 showsa facing zone 104 on a front face, FIG. 30 shows an “L” shaped facingzone 104, and FIG. 31 shows a facing zone 104 that surrounds base zone102. However, any bottom, side, and/or top of a zone molded product mayhave a facing side without departing from the invention.

The following is an example of two or more cementitious materialssupplied simultaneously to zoned mold cavities 906 with materialsentering the mold cavity via gravity, agitation, and/or vibration. FIG.32 shows mold zoning starting from hopper stage. The mold zoning processincludes a product transfer plate 902, on top of which the product isformed, and then transferred for curing. The process further includes aproduct mold 904, a first feed carriage 1000 which supplies a firstcementitious material 1002 from a first hopper 1004 to the product mold,and a second feed carriage 1006, which supplies a second cementitiousmaterial 1008 from a second hopper 1010 to the mold 904. Vibrationand/or vacuum means aids in materials densification, and ram head 1012aids product forming, providing product forming force, ram head 1012aids and “green” or uncured product ejection from the mold 904.

FIG. 33 shows the filling of feed carriage material cavities. In theembodiment shown, zoning of facing material 1008 is desired in thecenter of the mold 904 such that the non-facing material 1002 is dividedin two separate volumes. First feed carriage 1000 is divided into first,second, and third feed carriage cavities 1030, 1032, 1034. First feedcarriage cavity 1030 is filled with non-facing material 1002 viagravitational force, agitation within the feedbox (not shown), and/orvibration on the feed carriage 1000. Second feed carriage cavity 1032 isnot filled with non-facing material 1002 because a first feed carriagecavity seal 1040 prevents non-facing material 1002 from entering secondfeed carriage cavity, and third feed carriage cavity 1034 is filled withnon-facing material 1002 via gravitational force, agitation within thefeed carriage (not shown), and/or vibration of the feed carriage (notshown). Non-facing material 1002 is prevented from leaving first andthird feed carriage cavities 1030, 1034 respectively by second and thirdfeed carriage cavity seals 1042, 1044. Also second feed carriage cavity1032 is sealed by fourth feed carriage cavity seal 1046.

Similarly, second feed carriage 1006 contains a fourth feed carriagecavity 1052 which is filled with facing material 1008 via gravitationalforce, agitation within the feed carriage (not shown), and/or vibrationof the feed carriage (not shown). Facing material 1008 is prevented fromleaving fourth feed carriage cavity 1052 by fifth feed carriage cavityseal 1054.

In the embodiment shown. the feed carriages 1000, 1006 are filled bymaterial that flows from a hopper 1004, 1010 by gravitational force.Alternatively, material may be forced into the feed carriages 1000, 1006by an auger or other suitable means. Using an auger, for example, allowsa more precise amount of material flow into the feed carriages 1000,1006, which may result in more consistent products.

FIG. 34 shows the extension of feed carriages 1000, 1006 over the mold904. As the feed carriages 1000, 1006 move over the mold 904, first andsecond hoppers 1004 and 1010 are sealed in a manner common in theindustry that prevents material from falling out of the hoppers as thecarriages move into position over the mold.

One or more zone separator(s) 900 aids in creating zoned volumes andboundary layer bonding and extends from a device which is able totraverse over the mold 904 (as shown in this embodiment within the lowerfeed carriage), then extends the zone separators into the mold, retractsthe zone separators from the mold, and then is able to traverse awayfrom the mold. Extension/retraction means of zone separators 900 is notshown but may be mechanical, electro-mechanical, and/or pneumatic innature. Of course, any other suitable method for extending or retractingthe zone separators 900 may be used without departing from theinvention.

FIG. 35 shows the extension of zone separators 900 to the bottom of themold cavity 906. Also first feed carriage cavity seal 1040 enablesfacing material 1002 to enter second feed carriage cavity 1032 andfourth feed carriage cavity seal 1046 (shown in retracted position)enables facing material to enter the mold cavity 906. In general, feedcarriage seals have a translational and/or rotational motion and aremanipulated by mechanical, electro-mechanical, and/or pneumatic innature (not shown), but other means of actuation may be used withoutdeparting from the invention.

FIG. 36 shows second feed carriage cavity seal 1042 and third feedcarriage cavity seal 1044 in retracted positions, which enablesnon-facing material 1008 to enter the mold cavity 906. Similarly, fifthfeed carriage cavity seal 1054 is retracted, which enables non-facingmaterial 1008 to enter the mold cavity 906. It should be noted that lessthan fully unsealed feed carriage cavity openings may be utilized tocontrol material supply rates to the zoned mold cavities.

FIG. 37 shows that at or about the time both materials 1002, 1008 enterthe mold 904, the zone separators 900 may retract in a controlled mannerthat is consistent with: the viscosity of the mixture(s), vibrationfrequency, amplitude, and duration, less than fully unsealed feedcarriage cavity openings, agitation of materials, material supply ratesto the zoned mold cavities, and material levels in the zone moldcavities. The controlled retraction of zone separators 900 enhancesboundary 105 disruption to form boundary layer 106 and bonding ofmaterials 1002, 1008.

Placing the zone separators 900 at the bottom of the mold cavity 906initially creates a defined separation of materials on the futureexterior surface of the product being created. Once small amounts ofmaterials are present, zone separator 900 retraction can, if desired,exceed the height of material(s) levels in the mold cavity 906. Thistechnique aids boundary 105 disruption by having two or more materialsintermix prior to being exposed to significant vibration and/or formingforce and consequent material(s) densification to form boundary layer106. In other words, the materials should preferably be in contact witheach other in a low density state and then exposed to vibration and/orforming force to achieve intermixing and densification together.

In the present example, two or more materials should be approximately atthe same level with each respect to other. It should also be noted thatvibration of the mold can vary from no vibration—if materials can enterthe zone mold cavities without vibration, a small amount of vibration—toaid the zone mold cavities filling process, and a large amount avibration—to enhance the zone mold cavities filling process.

Aberrations in material filling and boundary layer disruption can beoffset by raking the material surface(s). Raking may be achieved byincluding prongs (not shown) protruding from the zone separator 900 intoeither one or all materials and in conjunction with the zone separatorsoscillating up and down, with a general retraction motion, can bothbreak up any cementitious film (thus exposing aggregate) andmechanically intermix materials.

FIG. 38 shows the zone separators 900 stopping at or near the top of themold 904 (future height of vibrated densified materials in the mold).Less dense material(s) from the feed carriages 1000, 1006 are added asmaterials become denser beneath them in the vibrating mold 904.

FIG. 39 shows the approximate end of mold material(s) filing process.Here the zone separators 900 are located approximately at the future topof the product 100 or top of the mold as densified by vibration. Hereless dense materials from the feed carriages 1000, 1006 moves into themold cavity 906 as materials within the mold cavity go through finaldensification and material filling.

As shown in FIG. 40, after the materials 1002, 1008 are deposited intothe mold 904, the feed carriages 1000, 1006 return to positions undertheir respective hoppers 1004, 1010 and ram head 1012 lowers onto themold to provide forming force. The forming force is typically completedin conjunction with vibration of the mold. While the forming force isbeing applied to the mold 904, materials 1002, 1008 are being resuppliedfrom hoppers 1004, 1010 to feed carriages 1000, 1006 so that the moldmay be filled again.

Turning now to FIG. 41, after the forming force has been applied, thetransfer plate 902 descends (relative to the mold) as the ram head 1012ejects the formed “green” or uncured product from the mold. Next, theram head 1012 retracts and a new transfer plate is inserted below thebottom of the mold. Meanwhile, the just formed “green” product moves toone or more curing area.

Agitators may be used to aid in the flow of materials 1002, 1008 fromthe carriages 1000, 1006 into the mold cavity 904. FIG. 42 shows detailof an agitator within the facing material supply cavity 924. The productis being formed on product transfer plate 902 within mold cavity 906.Within the mold 904, non-facing material 1002 is separated from facingmaterial 1008 by zone separator 900 which extends and retracts into themold cavity 906. In the embodiment shown, agitation of facing material1008 is achieved through linear and/or orbital motion of an agitator 901(linear shown). The agitator(s) 901 aids the entry of facing material1008 from the facing material supply cavity 924 into facing mold cavity908. Agitators may be similarly used with non-facing material from thenon-facing material supply cavity 926 to aid entry of non-facingmaterial into the non-facing mold cavity 910.

FIGS. 43A-B show two different styles of agitators. FIG. 43A shows arigid pin agitator 1030 used to aid material filling of the facing moldcavity. As the width of facing mold cavity decreases, material fillingmy be inhibited. FIG. 43B shows a flex blade agitator 1031 which may aidmaterial flow into facing mold cavities by “pumping” material with eachagitation motion cycle. In the embodiment shown, flex blade agitator1031 is made of stiff yet flexible material such as thick spring steeland flexes in the opposite direction of arm motion, but any othersuitable material may also be used. This flexing against the resistanceof a zero to low slump cementitious material aids the displacement ofmaterial into the facing mold cavity 908. The width of the flex bladeagitator 1031 may be a significant percentage of the width of the facingmold cavity 908 and thus directly displace materials from the facingmaterial supply cavity 924 into the facing mold cavity with agitationmotion. Additionally, to aid material filling of mold, agitator arm 1028may be lowered to enable an agitator 1030, 1031 to enter the moldcavity.

Turning now to FIG. 44, another embodiment of a molding process isshown. In FIG. 44, material is deposited from the carriages by meteringrollers 2000. Metering rollers 2000 are known in the art to allow aprecise amount of material to be deposited in a mold, which decreaseswaste and may result in a more consistent product. In the embodimentshown, the metering roller 2000 is driven by an electric motor (notshown). Other means of driving the metering roller 2000 may be usedwithout departing from the invention. Additionally, material levelsensors (not shown) may be located in one of more mold zone cavity toprovide real-time feedback to feed carriage cavity seal positions toadjust feed carriage cavity openings, vibration parameters, and/oragitation parameters, and control the metering roller 2000, and zoneseparator 900 positioning.

In the embodiment shown, metering rollers 2000 are deployed across theentire mold, but metering rollers may also be deployed to deposit onlyone or more zones as needed without departing from the invention. To aidfilling metering rollers 2000 may rotate in the same direction,different direction, and/or be stationary. Additionally, baffles may aidmaterial flow in the out of the metering roller 2000. Alternatively,material may be fed into the feed carriages 1000, 1006 using an augersystem such as the one described in U.S. Pat. No. 3,955,907, which isincorporated herein by reference in its entirety.

As described earlier, the multi-zone cementitious product 100 may beformed by any suitable means, including but not limited tomulti-forming, molding, or extrusion. Extrusion of a slab 162 mayenhance production efficiency by allowing slabs 162 to be made on amulti-forming machine 150 without core mandrels 170. Then, in asecondary process, the slab 162 is extruded through a die to create coreholes 410 in the slab.

In the system shown in FIGS. 45-48, a slab 162 without cored holes passthrough an extrusion chamber E180, which encases slab 162 and achievesfinal densification via vibration, vacuum, and/or forming force. Chamberbase E182 is stationary and chamber side walls E184 and chamber top E186are moveable to allow for slab 162 insertion. Once inserted, chamberside walls E184 and chamber top E186 are then set for “green” productlength and width dimensions. Note that in another embodiment of theextrusion chamber the settings for “green” product length and widthdimensions are completed prior to slab 162 insertion.

One end of the extrusion chamber E180 communicates with an extrusion dieE190 which in turn receives an end cap E192 and the other end of theextrusion chamber receives a ram E194 to supply final forming force.Chamber side walls E184 may also adjust for smaller or larger productlengths and one or more spacer may be added on the chamber base E182 orchamber top E186 for smaller and larger product widths. Any transferplate would be removed either before or after slab insertion to theextrusion chamber. The extrusion die E190 would be sized for eachproduct type and the inside height and width of the die would match theinside height and width of the extrusion chamber, potentially withspacers.

In the embodiment shown, the extrusion die E190 has extrusion mandrelsE196 held in place by mandrel extrusion support bar E198. Of course, theextrusion die E190 may be any shape or profile depending on theapplication without departing from the invention.

FIG. 48 shows one example of the operation of an extrusion chamber E180in accordance with the invention, which includes the following steps:(1) The slab 162 is inserted onto the chamber base E182, (2) the chamberside walls E184, and chamber top E186 are adjusted for desired “green”dimensions, (3) the chamber end cap E192 is placed over one end of theextrusion die, and a ram E194 is placed within the other side of theextrusion chamber, (4) a combination of forming vibration, vacuum,and/or forcing force complete product slab densification, (5) the endcap is withdrawn and the product slab is forced through the die toobtain core holes, (6) the ram is withdrawn, (7) the slab 162, nowhaving the shape of the extrusion die, is ejected, potentially on to atransfer plate, and accumulated for cutting. Of course, the dimension ofthe extrusion chamber E180 may also be fixed without departing from theinvention.

Although the invention has been herein described in what is perceived tobe the most practical and preferred embodiments, it is to be understoodthat the invention is not intended to be limited to the specificembodiments set forth above. Rather, it is recognized that modificationsmay be made by one of skill in the art of the invention withoutdeparting from the spirit or intent of the invention and, therefore, theinvention is to be taken as including all reasonable equivalents to thesubject matter of the appended claims and the description of theinvention herein.

What is claimed is:
 1. A multi-zone cementitious product comprising: abase zone made of a first cementitious material composition and forminga portion of the product; at least one facing zone adjacent to andbonded to the base zone, the at least one facing zone made of a secondcementitious material composition and forming at least one exterior faceof the product which is visible when the product is installed; adisrupted boundary layer between the at least one facing zone and thebase zone including material from both the at least one facing zone andthe base zone; the disrupted boundary layer bonding the at least onefacing zone to the base zone; and the at least one facing zone having athickness sufficient to prevent the base zone from being visible whenthe product is installed.
 2. The multi-zone cementitious product ofclaim 1, wherein the product is made using a dry cast process.
 3. Themulti-zone cementitious product of claim 1, wherein the product is madeusing a wet cast process.
 4. The multi-zone cementitious product ofclaim 1, wherein the at least one facing zone has a texture.
 5. Themulti-zone cementitious product of claim 1, further including a bondinglayer having a third material composition and disposed between the basezone and the at least one facing zone.
 6. The multi-zone cementitiousproduct of claim 1 having a first and second facing zone, the firstfacing zone having a first facing zone cementitious materialcomposition, the second facing zone having a second facing zonecementitious material composition.
 7. The multi-zone cementitiousproduct of claim 1 having a plurality of facing zones, each of theplurality of facing zones having a unique cementitious materialcomposition.
 8. The multi-zone cementitious product of claim 1, whereinthe product has core holes.
 9. The multi-zone cementitious product ofclaim 1, wherein the disrupted boundary layer is formed by vibrating andcompressing the multi-zone cementitious product.
 10. The multi-zonecementitious product of claim 9, wherein the disrupted boundary layer isnot parallel to the direction of vibration.
 11. A method for making acementitious product comprising the steps of: depositing a cementitiousmaterial onto a base conveyor in a material input section of amulti-forming machine; passing the cementitious material under a topformer, thereby forming an uncured slab between the top former, the baseconveyor, and at least one side conveyor; and ejecting the uncured slabfrom the multi-forming machine.
 12. The method for making a cementitiousproduct of claim 11 further including the steps of: providing a secondmaterial input section downstream of the top former; providing a secondtop former downstream of the second material input; depositing a secondcementitious material onto the uncured slab at the second materialinput; and passing the uncured slab and second cementitious materialunder the second top former which forms an uncured slab having twozones; cutting the slab to form an uncured cementitious product; andcuring the uncured multi-zone cementitious product.
 13. The method formaking a cementitious product of claim 12 further including the stepsof: inserting core mandrels onto the uncured slab before depositing thesecond cementitious material; and removing the core mandrels from theuncured slab before curing.
 14. The method for making a cementitiousproduct of claim 13 further including the steps of: forming furrows inthe uncured slab for receiving the core mandrels.
 15. The method formaking a cementitious product of claim 11 further including the stepsof: adding a texture to one or more faces of the cementitious productbefore curing.
 16. The method for making a cementitious product of claim12 further including the steps of: disrupting an exposed surface of theuncured slab before depositing the second cementitious material.
 17. Themethod for making a cementitious product of claim 11 further includingthe steps of: transferring the uncured slab to a coining chamber; anddensifying the uncured slab in the coining chamber.
 18. The method formaking a cementitious product of claim 12 further including the stepsof: applying pressure from the first and second top former to densifythe uncured slab before it is ejected from the multi-forming machine.19. The method for making a cementitious product of claim 11 furtherincluding the steps of: applying vibration to the uncured slab before itis ejected from the multi-forming machine.
 20. A method for making amulti-zone cementitious product comprising the steps of: preparing afirst cementitious material; preparing a second cementitious material;providing a molding machine including a mold with at least one moldcavity, a first and second hopper, and at least one feed carriage; theat least one feed carriage having a plurality of feed cavities; fillingfirst hopper with the first cementitious material; filling second hopperwith second cementitious material; transferring first cementitiousmaterial from the first hopper into at least one of the plurality offeed cavities; transferring second cementitious material from the secondhopper into at least one of the plurality of cavities; inserting atransfer plate under the mold; moving the feed carriage over the mold;inserting at least one zone separator into the mold cavity; depositingthe first and second materials into the mold cavity, the materialsseparated by the at least one zone separator; removing the at least onezone separator from the mold cavity; returning the feed carriage to aposition under the first and second hoppers; applying a forming force tothe mold to form an uncured multi-zone cementitious product; ejectingthe uncured multi-zone cementitious product from the mold onto thetransfer plate; and curing the uncured multi-zone cementitious product.